The Association Between Serum and Urine Zinc Concentrations and Recurrent Urinary Tract Infections in Children

Objective: Two major host factors in the pathogenesis of urinary tract infection are a defect in innate immune responses and a decrease in urothelial barrier function (UTI). Even in the cases of moderate zinc deficiency, innate and adaptive immune system functions are impaired. The aim of this study was to assess the association between serum zinc concentration, urinary zinc/creatinine ratio, and recurrent UTIs in children. Methods: In this study, children with recurrent UTIs and healthy children were enrolled. The patient group was divided into subgroups based on the nature of recurrent UTIs. Group 1 consisted of patients who had had >= 2 acute upper UTIs or 1 episode of upper UTI plus >= 1 episode of lower UTI. Group 2 consisted of the patients who had had >= 3 acute lower UTIs but no acute upper UTIs. The demographic characteristics, serum zinc levels, and urine zinc/creatinine ratios of the patients with recurrent UTIs were compared to those of the control group. Results: Thirty-three patients with recurrent UTIs and 33 healthy children were enrolled in the study. The mean serum zinc level and mean urine zinc/creatinine ratio of patients with recurrent UTIs were 6.6 +/- 1.66 umol/l and 16.44 +/- 13.04 umol/g, respectively. There was no statistically significant difference between patients and controls and between patients in Group 1 and patients in Group 2 in terms of serum zinc concentration and urine zinc/creatinine ratio, respectively. Conclusion: Further studies are needed to identify the impact of zinc deficiency on the recurrence of UTI in children.